Social media has been filled with videos from the war in Iran: explosions in the night sky, strikes in the distance, buildings reduced to smoke and debris. And then I came across something quieter: A woman standing on a balcony, holding her phone out over the edge as she records. “Hello, good morning,” she says, “It’s been a few days since I’ve shown you the daytime sky in Tehran.” The sky is blue with puffy white clouds. There’s a note of recognition in the voice, like seeing something she hasn’t in a while. For the moment, there are no flashes or muffled echoes of explosions, there are no screams, though she makes references to a difficult night before. “And here are the birds, still going on with their lives.” She says: “Tehran is quiet. The air is clean.”
Watching this video, I thought of my hometown from a lifetime ago. I lived in Tehran as an adolescent until I escaped through the Turkish border in the aftermath of 9/11. At the time, I feared the conflict might one day take the shape of open war between the countries I belonged to. With the help of the State Department, I was deported to JFK International Airport, where my mother was waiting.
But I still remember my time in Iran like yesterday. The complaint was constant: the smog. It hung over the city as both a fact of life and a failure of regulation and infrastructure, a failure on the part of the government. You could taste it some days. On others, it dulled everything at a distance, hiding the beautiful mountains just to the north of the city. Residents of Tehran have long been exposed to particulate pollution levels several times higher than global health guidelines—fine particles that penetrate deep into the lungs and bloodstream, contributing to respiratory and cardiovascular disease. Public health research has linked sustained exposure in Tehran to elevated rates of premature mortality, including impacts on infant health that echo across generations. The government tried to manage it in some ways. Pumping gas was restricted based on license plates to reduce overall emissions, odd-numbered cars on some days, even-numbered on others. I’m not sure how much that helped.
It is difficult to watch these videos now without thinking of the people still there. My father, two aunts and a wide network of cousins are living through this war in real time. The clarity in the sky as well as the explosions are not abstract to me. They exist in the streets I walked on, in the air my family breathes.
The video also reminded me of the early months of the COVID-19 pandemic—when cities around the world fell quiet and, almost overnight, the air cleared. People noticed what had been obscured for years. The absence was beautiful but deeply unsettling once you remembered why it was happening.
War is not often described in environmental terms, but it should be. Modern conflict is carbon-intensive at nearly every stage: the extraction and refinement of fuel, the manufacturing of weapons, the movement of ships and fighter jets across long distances, and perhaps more obviously: the detonation of explosives, the fires that follow and the long process of rebuilding all that has been destroyed.
In a paper published earlier this year, researchers said a single missile strike generates approximately 0.14 tons of CO2 equivalent—similar to driving a car for 350 miles. If strikes occur at the scale promised by Defense Secretary Pete Hegseth—a thousand targets per day—the emissions accumulate quickly into the hundreds of tons of CO₂ equivalent daily. Over the course of a month, that would place the carbon burden from missiles alone in the range of four thousand tons, even before accounting for the far larger emissions from aircraft, logistics, and infrastructure damage. For context, a single fighter jet can emit on the order of 15 tons of carbon dioxide per hour of flight, burning thousands of liters of jet fuel per hour, meaning just a couple of hours in the air can rival the emissions from hundreds of missile strikes.
We have some precedent for understanding the scale of what is happening now in Iran. Analysis of the war in Ukraine has estimated 77 million tons of CO₂ equivalent emissions the first year and a half of conflict (4.3 million tons of CO₂ equivalent per month), driven not only by military operations but by fires, reconstruction and the cascading effects of destroyed infrastructure. That accounting offers a sobering lens for what prolonged conflict in and around Tehran could mean environmentally.
And yet, within the city itself, something else is happening. Traffic has thinned to a fraction of what it was. Factories have shut down. Daily movement is limited. The steady emissions of civilian life (vehicles, industrial output and the background hum of a dense urban system) have dropped off sharply. The same forces that once made Tehran’s air feel perpetually heavy are, at least temporarily, absent.
What replaces them is harder to see, though not always harder to sense. Some emissions are displaced in time and space, such as fuel burned hours earlier by aircraft crossing long distances, supply chains operating far from the point of impact. Others are more immediate: the sound of fighter jets overhead, the thick columns of smoke rising from burning sites. Footage from just south of Tehran showed a refinery struck and burning, sending a dense plume of black smoke into the sky. Large refineries can emit about 1.5 million tons of CO2 per year, according to a 2023 study. This suggests that fires like the refinery blaze circulating on social media can release thousands of tons of CO₂ equivalent depending on duration and intensity, along with a complex mix of particulate matter, heavy metals and toxic compounds that linger long after the flames subside. War does not reduce emissions. It rearranges them.
The environmental damage extends beyond carbon accounting. Explosions release heavy metals and fine particulates into the air and soil. Fires can burn for days, spreading pollution across wide areas. Damaged infrastructure—water systems, industrial facilities energy networks—can leak contaminants that take years to remediate. These effects accumulate quietly, embedding themselves in ecosystems and in human health.
Even as we attempt to track emissions elsewhere, war remains difficult to see in our climate ledgers. Frameworks informed by bodies like the Intergovernmental Panel on Climate Change (IPCC) provide guidance for national reporting, but the environmental costs of military activity, particularly across borders, are often inconsistently captured or obscured. As one study observed, IPCC guidelines do not explicitly consider wartime greenhouse gas emissions reporting, meaning that some of the most carbon-intensive activities on Earth are only partially captured—if at all—in our climate ledgers.
And still, for a moment, the sky is blue. It is possible to understand why someone would notice. Why they would say it out loud. Why, even with the knowledge of what is unfolding across the city, they might want to capture that moment of calm and blue sky. Toward the end of her video, she says, “I hope that all of us, wherever we are in the world—those who miss this land and this air—find a way to endure. I hope that Iran survives. That Tehran survives. And that all of us can be happy again.” The sky above her is clear. It is a clarity that carries no comfort.
Daryush Nourbaha is a graduate of the M.S. in Sustainability Science program, which is offered by Columbia’s School of Professional Studies and the Columbia Climate School. He is currently an environmental, health and safety leader in New York City.
Views and opinions expressed here are those of the authors, and do not necessarily reflect the official position of the Columbia Climate School, Earth Institute or Columbia University.
